god damn. this is actually something i think my rashmi build would benefit from. it at least bears testing. i run a huge amount of counterspells and very few wincons, in most cases this will be a 3/3 for uu thats returning those counterspells

I love this use of delve. It's balanced, too, you only get one back at a time and it'll fall to most removal and blockers so it's both slow and somewhat vulnerable. You are pretty much guaranteed to get one card back, so it may be more important to assess this as if you'll typically only get that first card back and cards 2-4 are just gravy. If you even delve for the full four to begin with. I'm going to be aiming for 2UU or 1UU more often than not, and it's still great even then.

I think this card becomes an easy 1/2-of in Legacy U/R Delver. You aren't running black for Anglers, so aside from maybe a couple snaps/arcanists you don't really have any use for cards in your GY. I can see a lot of games where you cast this on turn 5 or something exiling something like land, land, force, ponder, and if your opponent doesn't kill it right there, you'll just run away with the game.